Such a device is known from EP 0 828 629 B1. There it is proposed that an elongated cantilever be placed in the transition area between the rigid contact line system and the elastic contact line system. The mechanical rigidity of the cantilever increases constantly from its free end to a clamped-in rigid end, wherein a continuous contact wire is conducted from the elastic contact line system to the rigid contact line system and is affixed to it by clamping over the entire length of the cantilever. The cantilever is mechanically and electrically coupled with the power track by fishplates, which are located in the interior of the profiles of the cantilever and a rigid power track.
Rigid contact line systems with power tracks are mostly used on sites with limited spatial situations, such as in tunnels or superstructures, since they require a lower system height. Elastic contact line systems have contact wires defined by European norms, which wires are suspended on a carrier cable by means of suspension wires that are suspended at short intervals, wherein the carrying points on the carrier cables are approximately 30-180 cm higher than the contact wire. Furthermore, the contact wires and carrier cable are mechanically tensioned with approximately 8-30 kN, so as to permit abrasion rates up to 500 km/h by the current collectors of electrically driven vehicles, in particular, rail vehicles. The necessary clamping devices are complex units, which are difficult to place, in particular, in underground tunnel routes.
With the cantilever, an elastic transition or coupling area is implemented, whose elasticity increases from its current track-side fixed end to the contact line-side free end. The coupling site between the rigid and flexible contact line parts is thus distributed over a larger distance, wherein the alternating bending stress of the contact wire that arises as a result of the interaction between the current collector and the contact wire is distributed over a greater mechanical length and thus is better dampened. The risk of fatigue breaks on the contact wire is greatly reduced as a result of the elastic coupling.
In actual practice, however, it has become evident that the device in accordance with the state of the art is only conditionally suitable for multiwire contact lines. Direct current railway systems and metro lines frequently use two parallel contact wires in the elastic area of the contact line systems, in order to be able to control the high currents of up to 4000 amperes with the low supply voltages of 750-1500 volts. In the transition range, this would also require three cantilevers conducted parallel to the contact wire of the rigid current track. A solution in which the two contact wires of the elastic drive system were only connected directly with the free end of the cantilever that holds the contact wire of the rigid contact line system has proved a failure in in-house experiments conducted by the applicant, because of the dynamic behavior.